No other data on the W diffusion activation energy in EUROFER could be found in the literature, but there is some data for the activation energy for W diffusion in Fe available.
All of the reported experiments are done at considerably higher temperatures (>1000K) and analysed either by electron probe micro analysis (EPMA) or by measuring radioactive tracer isotope diffusion.
In these studies activation energies of 2.47eV [1]}, 2.97eV [2]}, and 2.61eV [3]} are obtained.
Compared to the present results, these are significantly larger values.
There are various factors which might contribute to the different behaviour.
On the one hand, EUROFER is a more complex alloy with multiple constituents.
On the other hand, the microstructure may play a decisive role.
The EUROFER samples have small grains in the m range as is shown in figure REF .
The Fe samples investigated in the referred diffusion studies are carefully annealed and have a different structure with larger grains.
An enhanced grain boundary diffusion in EUROFER could be responsible for the observed much lower diffusion activation energy
